Abstract: According to the TGA results, the temperature requirement of the activated carbons modifying process was discussed. Boehm titration, Fourier transformed infrared spectroscopy(FTIR) and BET surface area measurement were used in measuring surface physicochemical properties of these modified activated carbons. Then, Fixed-bed adsorption experiments were conducted under the same experimental conditions at 283K, with acetone, dichloroethane and methanol being as adsorbents, respectively. After the correlation analysis of experimental results and test result, the calculation of dynamics parameters and adsorption energy was conducted. The results show that the pore size distribution and surface functional groups of thermal-modified activated carbon are different from the unmodified one, and the relationship of adsorption capacity and effective pore volume is linear. The adsorption process of four absorbates on activated carbon can be described by the pseudo-first-order and pseudo-second-order kinetic equation. Also, intra-particle diffusion model shows that the rate of adsorbing the organic gases of activated carbon is greater than unmodified one. The adsorption energy of all the four chosen adsorbents is smaller than 20 kJ?mol-1, which indicating that the adsorption of the four adsorbents on activated carbon is dominated by physical adsorption.

Key words: activated carbon, thermal treatment, adsorption kinetics, adsorption energy

摘要： 根据热重分析结果，确定了活性炭热改性的温度条件；采用Boehm滴定、傅式转换红外光谱仪（FTIR）、比表面积分析仪对活性炭表面物化性质进行了测试；以甲苯、丙酮、二氯乙烷、甲醇为吸附质，在283K下进行了固定床吸附实验，探讨了改性前后活性炭表面结构变化与吸附量之间的关系，同时计算了相应的动力学参数和吸附能。实验结果表明，热改性可以改善活性炭的孔径分布和改变表面官能团的分布，吸附量与有效孔容呈明显的线性关系；一阶动力学方程和二阶动力学方程均可描述四种吸附质在活性炭上的吸附过程；孔内扩散模型表明改性活性炭对有机气体的吸附速率均大于未改性活性炭；四种吸附质在活性炭上的吸附能均小于20kJ?mol-1，表明活性炭对四种有机气体以物理吸附为主。

关键词: 活性炭, 热改性, 吸附动力学, 吸附能